Manufacture of paint for protecting iron, wood, and the like from sea growths.



UNITED STATES PATENT OFFICE.

MARINUS'RATPARD, OF DEN HELDER, NETHERLANDS.

MANUFACTURE on PAINT FOR rno'rno'rme momwoon, AND THE LIKE rnoM sna GBOWTHS.

1,108,395, Specification of Letters Patent.

No Drawing.

To all. whom it may concern:

Be it known that I, MARINUS RAPPARD, subject of'the Queen of theNetherlands, residing at Den Helder, Kingdom of the Netherlands, haveinvented certain new and useful Improvements in the Manufacture. ofPaint for Protecting Iron, Wood, and the like from Sea Growths, of whichthe following is a specification.

The present invention relates to the manufacture of a paint to beapplied to iron, wooden or the like surfaces, to protect them from thedestructive action of sea-growths.

Of all known coatings or coverings the only one which afi'ords any realprotection against sea growths is a coating ofplates of copper andwooden vessels have been so protected with great success, the plateshaving remained eflicient for many years. Red cop-per plates have alsobeen applied to iron vessels, but in order to prevent the galvanicaction arising between the iron of the ships skin and the copper and toenable the plates to'be properly attached a layer of insulating materialhad first to be applied to which the copper plates could be readilyattached. This method, however, was very' expensive and is no longerused andreliance is placed solely upon paints for protecting iron ships.

The paints which have hitherto been used lose their power after a shorttime, so that the ships have to be re-coated at regular intervals afterthe removal of any growths which may'have accumulated and this also isexpensive. It has also been proposed to.

prepare paints of an alloy of copper with another metal or other metalsin a finely divided form mixed with a suitable fluid me dium, or tospread'or distribute pulverized copper, or an alloy thereof, on ananti-fouling paint before the latter has become hardened or set. Thecopper powder is sometimes mixed with anti-fouling paint (lead-.

paint) before being applied to the ships hull, either with or withoutthe subsequent application of'pulverized copper or an alloy thereof.Another paint for reventing the fouling of ships bottoms or t e like, isprepared by mixing .pulverized copper with pulverized. red lead "andincorporating this mixture in a vehicle consisting of a solution ofcaoutchouc in oil or turpentine or other suitable solvent, boiledlinseed oil and common rosin. .It has also been proposed to suspend zincin a semi-saturated solution of sulfate of copper and to mix the depositafter pulverization, with Chinese varnish, or to mix finely dividedmetallic copper or an alloy thereof with a vehicle derived from thesludge oil resulting from the refining of petroleum.

According to thepresent invention a paint is manufactured which isintended to form a coating of copper on the ships skin in such a mannerthat it has the same properties with respect to sea growths as the redcopper plates have, and at the same time prevents the galvanic actionbetween the ships skin, and the copper coating. This paint consistsmainly of copper in finely powdered form mixed in suitableproportionswith shellac in combination with oil (preferably linseedoil), this combination being most suitable owing to its high bindingpower and insulating qualities and also the rapidity with whichit driesin the air. The copper powder may be made from pure copper or from analloy containing a high percentage of copper.

The paint may be made in any suitable manner, for instance byfirstdissolving the shellac in alcohol, and then adding the copper and oilwhile the mixture is continuously stirred. Suitable mixtures contain 3-6parts by weight of copper powder, 1-2.5 parts of dry shellac dissolvedin 3 7 parts of alcohol and 3.58.75 parts of oil. If the paint is madein this way each particle of the copper receives a coating of shellacand oil, so that on applying the paint, to the surface of the ship aninsulating layer between the latter and the copper is formed, while theprotective action of the copper against sea-growths is ]'not affected bythe shellac and oil.

To enhance the insulating effect a coating of zinc or a zinc compoundand oil or shellac Patented Aug. 25, 1914. Application filed October 7,1912. Serial No. 724,431.

parts of alcohol, and 8.5-8.75 parts of a siccative oil.

2. A paint containing finely-divided metal containmg a high percentageof copper, mixed and suspended in an alcoholic solution of shellac and asiccative oil.

In testimony whereof I have hereunto set my handvin presence of twosubscribing witnesses.

. MARINUS RAPPARD.

Witnesses "W. on MAAN, F. W. DAENDELS.

